I have a 1988 900c (with carb). Great car, but very noisy (as usual) above 120 kph (> 75 Mph). I was wondering if engine mount replacements (or: upgrade?) would be of any help? Can I move to rubber or even hydraulic?

Well, the noise is nothing special. It's just loud... I think that is not an exception for older cars, but the motor humming is really louder than in a Fiat Uno or any of the smaller/cheaper cars like that.

I'll better check the engine mounts, as you said. b.t.w.: I don't expect we have the same cars: min is not a turbo, it is just the basic 2 liter carburettor fuelled thing. I believe it is the least among its equals... (Although, it has power steering and Airco...)